crispy_wafer

If you take the approach above, i'd pile up the PIR and sell it, facebook marketplace, someone will have it, and you'll get some money back. Couple or 3 boards for £20 or so, I found people are fitting it into sheds, and allsorts when I sold a load of offcuts over autumn/winter last year..

if you know the buildup then get onto ubakus , this will help you model

here's the MI's - page 9 up to you and your builder to decide whether installation instructions have been followed. Cavity Wall Specification Guide Recticel Insulation.pdf

They/you both need to understand how the insulation works here to get the best performance for your wall, the recticel board and inner block need to act as one, so insulation board tight to the block please, if there are gaps between board and block then draughts in the cavity will wick the any heat you put into the structure away from the blockwork. Don't be afraid to speak to your guys about this, now, it's not too late to rectify.

we are coming in around 3k for our mvhr. Could have been more if I wanted plaster in terminals, could have been less if I had a central design rather than in the loft with 2*75mm runs to all terminals. I don't know the scale of your build, but I'd baulk if someone quoted 10k to me! Like many on here I have no loyalty or trust in any one company, shop about to secure savings, I'm pretty sure there's a thread somewhere in here where many have shared the companies they'd used for parts and bits.

clean out as above, squirt or two of ct1 behind, then a couple of bits of battening screwed to wall horizontally over the capping as a temporary prop till the ct1 goes off

Slightly different take, I've installed a couple of ducted FCU's in the loft space and one in the base of a cupboard, supply and extract ducting traversing loft spaces and eaves to the bedrooms and downstairs. Mine are A2A rather than A2W units though.

I've went a bit overkill 400's with 15mm, I battened with 22*100 sawn and plastic shims to take out the dips.

just been at the backer boards in the bathrooms, already getting ocd with the straight edge. I wont be tiling no way, absolutely not. Tried dot and dabbing at the weekend, did one wall, came out alright, got brave and went to do another, about perfectly flat, but 5mm out of plumb, that's it, not doing anymore cant face it! I've had a go, so now the pro's can do the rest.

yep 🤣, usually have a few going round my head at any particular moment during the build.

Yes, I did too. Fill the space the best you can, full sheets staggered, then half sheets and offcuts to fill remaining spaces. Square edges get most joints nice and tight. Any rocking will get flattened out with screed, foam any gaps where you cannot realistically fit insulation. Don't worry too much about it, you are not aiming for instagram/marketing levels of finish, do the best you can, then get it covered over with plastic sheet and crack on with the UFH if that's your path.

Speak in person to the merchants to get best prices. Do a rough work out of qty's and get yourself a baseline price. Also, make sure your builders would be ok with you purchasing materials!

if you want to run a cable for future use, I'd either run a duct so you can pull a cable at a later time, or get a heat loss calc done so you can quickly spec up the right size range HP and what it's cable size requirements are before you start pulling cables.

Nah, a squirt in the end about 30mm or so each end and a very quick trigger, how far into the conduit the foam spreads I don't know. once two cables are in, the nozzle will only go so far.

That's a useful tip/thought. How deep would you say the track is on your blinds? I meant the inner leaf, but yes your point is valid and stands. The reveals are taped over and the corners painted with soudatight. I have 80mm to play with, so if I want 40mm frame to sash, 15mm plasterboard (got a pile of 1200mm offcuts to use up) + skim leaves me with 20mm or so to insulate behind. I've over ordered on the jackoboard, would this do?, or should I PIR it - guess I could ct1 insulation to the PB, I've got some sheets of 20mm left over from when I did the screed perimeter? Sounds like you had fun achieving that...

yep, then ct1 over each end, if insects want to get in they are gonna need strong digging tools

my confusing wording wont be helping 🤣, yes to window reveals. Lets say before plasterboard I have an 80mm of frame on show from block to the bit that moves when you open the window. I was thinking after boarding to leave myself 45mm of frame showing? Would that be too little, too much, or just about right?

Good Morning, Probably sounds a bit of a daft question, I'm prepping for boarding my window reveals, how much space should I leave between the edge of the window and the plastered face of board? Would you make the head same as the sides? Thanks Marek

Ta muchly, cable ran, that’s saved me from dog house.

Morning all, In my excitement of boarding up have forgotten to wire in another switch to control a separate light. Situation is a Bedroom with wall lights either side of the bed, each side have its own switch to control it’s side light. Now I’ve ran the looped in cable to switch 1 on one side and ran the loop out cable to another room and totally forgot about switch 2. Can I run a 2nd cable to loop out again from bed switch 1 to bed switch 2. thx marek

I’d give the top of the plasterboard a knock with the side of your hand or a fist , you should be able to hear/feel where there is adhesive, sounds are different to where there is none.

What kind of pozi’s, are they the metal web jobs or the I beam type? The metal web jobs are a PITA, to get between the webs on the joist without making a mess of your hands, or material, it’s doable of course just increases the amount of labour time to do it right without gaps etc. Just my thoughts just so you go into this with eyes open!

@Iceverge I need to get hold of some of these J beads for my window reveals, do you have a picture of what they look like? I mean if I go into the merchants and ask for j bead, I want to end up with the right stuff!

You’ve got ventilation going on above the roof insulation which is good, however the detailing of the pir install is not so good, which may well be allowing this ventilation a path down behind the plasterboard. For me, the gaps need filling then taping over before any hint of the ceiling plasterboard goes up. Because there are gaps the cold outside air is making its way round the plasterboarded wall. Tiles off or ceiling down. Fill the gaps, tape up jobs a goodun. Save it for the summer though A common method for fixing the plasterboard not having continuous ribbon of adhesive round the perimeter of each board is to drill a series of holes at specific intervals and squirt a low expansion foam (Illbruck or soudal) what have you got on the ceiling? Is it insulated board or just regular board? needs rectifying really, don’t want to say you’ll end up with mould issues but it’s possible where the colder spots are.

Don’t worry, part of the ahem ‘fun’ going back and doing a bit of rework. It’s how we learn